I stayed 4 nights in Gerd's condo and it is simply fantastic. The location of the building could't be any better. It is located between Nana and Asok BTS stations, close to soi 11 which has many bars and restaurants, and close to shopping malls and shops. The building has a pool, gym, minimarts, and all you need.
The condo itself is very nicely decorated and has everything from wifi, large TV, lots of room to store your clothes, and even has a washer and dryer whuch is quite helpful.
Gerd is very helpful and is always available if you have any questions or concerns during your stay. I will definately stay there again when I return to Bangkok.